Many web sites on the Internet World Wide Web regularly display advertisements. The particular advertisement that is displayed when a viewer accesses a web site can either be stored locally on the web site or it can be stored on a central server. As used herein the term viewer refers to an individual who views or looks at a web page using a program such as one of the commercially available web browsers.
The Hyper Text Transfer Protocol (HTTP) and the Hyper Text Mark Up Language (HTML) provide a mechanism whereby one website can easily link to a remote server. The HTTP mechanisms for referencing and obtaining material from a remote server is useful in providing advertising material for display to viewers. There are commercially available systems that provide advertising material for web sites from a central server. Various web pages have links to this central server. With such an arrangement, when a viewer accesses a particular web page, a central server provides an advertisement that the viewer seeks on the web page.
Using standard HTTP facilities it is possible to track when a particular viewer accesses a web site and thus it is possible to compile a data base which in essence provides a profile of the sites a particular viewer has accessed using the same browser. Furthermore it is known that types of viewers generally access particular categories of web sites. The capabilities inherent in the World Wide Web for tracking the sites that a viewer has seen provides a mechanism for targeting particular advertisements to particular types of viewers.
There are prior art systems that provide advertisements from a central server that has a database of information on viewers. A database of viewer information can be compiled from a variety of sources including information about a viewer that is available when a viewer accesses a server. In such prior art systems, the characteristics of the viewer as provided by the data base of viewer information determines the particular advertisement which is displayed when a particular viewer who accesses a web site. Other information such as the characteristics of the web site can also be used to determine which advertisement a viewer will see when a web site is accessed. Using such systems advertisers can target advertisements by criteria such as web site category, geographic location of the viewer, the operating system of the viewer's computer, the type of browser which the viewer is using, the internet domain type of the viewer, etc.
Advertisers who use such prior art systems must specify in advance, the targeting criteria they want to use for their advertisements. The central server the provides advertisements to viewers based upon: (a) the targeting criteria established by the advertisers, (b) the information which the central server has in its data base concerning the particular viewer; (c) information about the web site that has been accessed by the viewer, and (d) other information available to the central server such as the time of the day.